mod_access_referer allows/denies access based on what page is shown in the Web browser, which means that if you publish a document (picture, chart, or other) in your site, the people will have to visit your Web site to access it, and no one will be able to link just the document.

Log4j is a logging package written in Java. Log4j allows you to log to a file, a java.io.Writer, a remote server, or a syslog daemon. The package is designed so that log statements can remain in shipped code without incurring a high performance cost. One distinctive feature of log4j is the notion of hierarchical loggers. Using hierarchical loggers, it is possible to select (at runtime) which log statements are output at arbitrary granularity. Users can choose to implement their own log formats and output strategies.

Apache Jetspeed is an Enterprise Information Portal that allows users to aggregate and organize various information sources and present them in a multi-device, user-customizable Web interface. It integrates a simple syndication system based on OCS and RSS formats.

mod_backhand is a load balancing module for Apache. It provides per-request HTTP redirection within a heterogeneous Apache server cluster. Each request is processed and run through a set of "candidacy functions" to determine which server is best suited to respond. The request is then proxied to that server. Facilities are in place to allow you to write your own dynamically loadable decision making algorithms. Everything about the request and the current availability of resources can be used in the decision-making process.

auth_ldap is an LDAP authentication module for the Apache Web server. Auth_ldap
has excellent performance, due to its use of aggressive client-side caching
algorithms. It also has support for LDAP over SS or TLSL. It also features a
mode that lets Microsoft Frontpage clients manage their Web permissions while
still using LDAP for authentication.

The Apache JMeter is a 100% pure Java desktop application designed for performance and load testing of servers. It was primarily designed for Web/HTTP testing but it has been expanded to include support for a variety of testing modules. It ships with modules for HTTP and SQL databases (using JDBC). It may be used to test server performance both on static and dynamic resources, to simulate a heavy load on a server or network to test its strength, or to analyse overall performance under different load types. It also provides pluggable interfaces for customizing data visualization, test synchronization, and the construction and execution of tests.

Apache Cocoon is a Web development framework built
around the concepts of separation of concerns and
component-based Web development. Cocoon
implements these concepts around the notion of
"component pipelines", each component on the
pipeline specializing on a particular operation.
This makes it possible to use a Lego(tm)-like
approach in building Web solutions, hooking
together components into pipelines without any
required programming.

When building server side applications for the Web, independently of the language used (Java, PHP, Perl, etc), a lot of time is spent writing embedded HTML code and dealing with the fact that HTTP is a stateless protocol. SPFC allows you to write HTML forms like you write a Java GUI.